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51.
52.
Dejan Orlic Bernhard Reimers Goran Stankovic Nicola Corvaja Alaide Chieffo Flavio Airoldi Vassilis Spanos Luca Favero Carlo Di Mario Antonio Colombo 《Catheterization and cardiovascular interventions》2003,60(2):159-166
The purpose of this study was to evaluate the safety and efficacy of the new Fox Hollow atherectomy device (FHT) designed for more efficient and easier plaque removal. The FHT has short rigid section and low-profile cutter mounted on a monorail catheter. The FHT catheter was utilized in 77 patients with 98 lesions. Mean reference vessel diameter was 2.75 +/- 0.51 mm. Successful atherectomy with tissue retrieval was performed in 94 lesions (96%). Following atherectomy, mean diameter stenosis was reduced from 71.1% to 31.9% and further to 10.4% following adjunctive treatment. Angiographic complications were one coronary perforation and one adventitial staining, both successfully treated with prolong balloon inflation and stent implantation. Nine patients (11.7%) had in-hospital non-Q-wave myocardial infarction (MI). One patient died (1.3%) for noncardiac reasons and one had MI (1.3%) at 6-month follow-up. Target lesion revascularization was required in 13 (13.8%) lesions and target vessel revascularization in 15 (20.3%) patients. There was target vessel failure in 17 (23.0%) patients. Plaque debulking with the FHT catheter can be performed safely and effectively in relatively small vessels and complex lesions located in mid-distal artery segments with 6-month clinical outcome similar to prior atherectomy devices. 相似文献
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BACKGROUND: In case of severely calcified ascending aorta, modified operative strategies are required in order to avoid manipulations of the aorta and minimize subsequent cerebral vascular accidents. CASE REPORT: A 73-year-old woman, with a coronary two-vessel disease and aortic stenosis was scheduled for coronary artery bypass grafting and aortic valve replacement. Due to severed calcification of the ascending aorta including the transverse arch, neither cannulation, clamping nor incision of the aorta or its replacement was feasible. Therefore bypass operation was performed using a modified approach. After 1 month, implantation of a valved conduit between the left ventricular apex and the descending aorta through a lateral thoracotomy followed. CONCLUSION: Only in few cases the surgical treatment of a coronary artery disease in combination with left ventricular outflow tract obstruction and heavily calcified ascending aorta has been described. Undoubtedly, creation of an apicoaortic connection is today only indicated in the adult population in a small collective with multiple previous operations or porcelain aorta. 相似文献
55.
Konstantin Musiychuk Natalie Stephenson Hong Bi Christine E. Farrance Goran Orozovic Maria Brodelius Peter Brodelius April Horsey Natalia Ugulava Abdel‐Moneim Shamloul Vadim Mett Shailaja Rabindran Stephen J. Streatfield Vidadi Yusibov 《Influenza and other respiratory viruses》2007,1(1):19-25
Historically, most vaccines have been based on killed or live‐attenuated infectious agents. Although very successful at immunizing populations against disease, both approaches raise safety concerns and often have limited production capacity. This has resulted in increased emphasis on the development of subunit vaccines. Several recombinant systems have been considered for subunit vaccine manufacture, including plants, which offer advantages both in cost and in scale of production. We have developed a plant expression system utilizing a ‘launch vector’, which combines the advantageous features of standard agrobacterial binary plasmids and plant viral vectors, to achieve high‐level target antigen expression in plants. As an additional feature, to aid in target expression, stability and purification, we have engineered a thermostable carrier molecule to which antigens are fused. We have applied this launch vector/carrier system to engineer and express target antigens from various pathogens, including, influenza A/Vietnam/04 (H5N1) virus. 相似文献
56.
Van Geertruyden JP Ntakirutimana D Erhart A Rwagacondo C Kabano A D'Alessandro U 《Tropical medicine & international health : TM & IH》2005,10(7):681-688
OBJECTIVES: The aim of the study was to assess the knowledge, attitude and practices of pregnant women towards malaria and their association with malaria morbidity. METHODS: Cross-sectional malaria survey of 1432 pregnant women attending six health centres, each of them situated in a specific health district in Rwanda from September to October 2002. RESULTS: The overall prevalence of malaria infection was 13.6% and all infections but two were caused by Plasmodium falciparum. The six health districts were significantly different in terms of malaria prevalence, which varied between 11.5% and 15.4% in four and was <5% in the other two districts. The prevalence of anaemia and splenomegaly mirrored that of malaria infection. In three districts, the prevalence of infection was significantly higher in primigravidae than in secundigravidae and multigravidae (P = 0.01), while in two others it did not vary with parity. Bed net use was low - only 13.1% of the women had at least one bed net at home and 8.3% of them slept under it - and significantly different between districts. Most women knew that malaria might have serious consequences for their pregnancy and that insecticide-treated bed nets are useful for malaria prevention. However, the bed net market price [1525 Rwandan Francs (RFr), approximately 1.6] was much higher than that considered as affordable and acceptable (389 RFr, approximately 0.3). CONCLUSION: Malaria in pregnancy is a major problem in Rwanda, even in the districts of low transmission. Bed net use among pregnant women is low. The option of providing free insecticide-treated bed nets to pregnant women should be explored and possibly implemented; it could rapidly increase bed net use and earlier attendance to antenatal clinics with clear benefits for the women's health. 相似文献
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Satyan S. Kalkunte Stefan Neubeck Wendy E. Norris Shi-Bin Cheng Stefan Kostadinov Dang Vu Hoang Aftab Ahmed Ferdinand von Eggeling Zahir Shaikh James Padbury Goran Berg Anders Olofsson Udo R. Markert Surendra Sharma 《The American journal of pathology》2013,183(5):1425-1436
Preeclampsia is a major pregnancy complication with potential short- and long-term consequences for both mother and fetus. Understanding its pathogenesis and causative biomarkers is likely to yield insights for prediction and treatment. Herein, we provide evidence that transthyretin, a transporter of thyroxine and retinol, is aggregated in preeclampsia and is present at reduced levels in sera of preeclamptic women, as detected by proteomic screen. We demonstrate that transthyretin aggregates form deposits in preeclampsia placental tissue and cause apoptosis. By using in vitro approaches and a humanized mouse model, we provide evidence for a causal link between dysregulated transthyretin and preeclampsia. Native transthyretin inhibits all preeclampsia-like features in the humanized mouse model, including new-onset proteinuria, increased blood pressure, glomerular endotheliosis, and production of anti-angiogenic factors. Our findings suggest that a focus on transthyretin structure and function is a novel strategy to understand and combat preeclampsia.Preeclampsia occurs in 5% to 8% of pregnancies worldwide and is a major cause of fetal and maternal morbidity and mortality.1–3 It is a heterogeneous disease with varied presentations from mild self-limited hypertension and proteinuria to severe forms with significant end-organ dysfunction and HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets).3 Although the cause of preeclampsia and its appropriate treatment remain elusive, this syndrome has been proposed to reflect at least two stages of complications during pregnancy. These begin with preclinical manifestations at the maternal-fetal interface, followed by systemic clinical symptoms.1,2 Hypertension, proteinuria, and edema, with a variable degree of fetal growth restriction, are the cardinal features of preeclampsia.3 Because the placenta is the nutritional and immunological gateway to normal fetal development and pregnancy outcome, placenta-related events are believed to be central to the pathogenesis of this disease. Evidence exists for the release of disease-initiating molecules into maternal circulation that triggers the clinical symptoms.1,4 Placental and systemic anomalies reflected by circulating placental debris, inflammation, impaired remodeling of spiral arteries, placental hypoxia/ischemia, excess production of anti-angiogenic factors [soluble fms-like tyrosine kinase-1 (sFlt-1)], and soluble endoglin (sEng), and angiotensin receptor autoantibodies have all emerged as contributors to the pathophysiological characteristics of preeclampsia.2,4–14Preeclampsia has remained enigmatic because of lack of well-defined etiology and animal models. Although normal mice do not develop preeclampsia spontaneously, mouse models have been judged to be particularly useful to uterine diseases and pregnancy complications because many similarities in female reproduction and placentation have been identified between the two species.15 Moreover, their tractable genetics provide an effective way to probe mechanisms more deeply than many other species.15–17 We recently showed that sera from preeclamptic women could function as a source of novel causative factors that induced hypertension, proteinuria, and kidney pathological characteristics, as well as intrauterine growth restriction (IUGR), in IL-10−/− mice in a pregnancy-specific manner.18 IL-10 functions as a potent vascular and anti-inflammatory cytokine and has been shown to be present at significantly reduced levels in preeclampsia placental tissue.19,20 Preeclampsia serum (PES) was found to disrupt endovascular cross talk between trophoblasts and endothelial cells and to induce placental hypoxia and excess production of sFlt-1 and sEng,18 soluble factors known to precipitate maternal symptoms.21,22 These results from our serum-based humanized mouse model suggest that the pathophysiological characteristics of preeclampsia are more complex than previously thought and are likely to involve interactions and dysregulation of multiple factors. By using serum proteomic screening by surface-enhanced laser-desorption ionization-time-of-flight (SELDI-TOF), our results suggest that PES contains a reduced abundance of transthyretin, a plasma transport protein for the thyroid hormone, thyroxine, and retinol-binding protein.23 More important, transthyretin has been widely studied for its role in amyloid diseases associated with protein misfolding and aggregation, resulting in deposits of toxic, fibrillar aggregates in specific organs.24–26 Dysregulated or reduced transthyretin has also been implicated in Alzheimer disease, and overexpression of a wild-type human transthyretin transgene has been shown to ameliorate the disease in the transgenic murine model of human Alzheimer disease.27,28 Transthyretin in its native form assumes a homotetrameric quaternary configuration (approximately 14 kDa per monomer). Post-translational modifications of the monomer result in detection of several isoforms.29 Circulating transthyretin is also a validated marker of malnutrition and has a putative role in oocyte maturation and inflammation.30–32 Although the presence of transthyretin during implantation in mice and in the placenta and trophoblasts in humans has been reported,33,34 its functional role in normal pregnancy or adverse pregnancy outcomes has not been recognized. We hypothesize that transthyretin in preeclampsia is structurally and functionally dysregulated and contributes to the onset of this serious pregnancy complication. Herein, we present complementary in vitro and in vivo approaches, which show that endogenously altered transthyretin is a preeclampsia-causing agent and that native transthyretin has the ability to block the onset of preeclampsia-like features. 相似文献
59.
Stanislava Erdelja Petra Vokal Marija Bolfan Sergej Augustin Erdelja Branka Begovac Ivan Begovac 《Croatian medical journal》2013,54(5):460-468
Aim
To assess the relationships between delinquency and demographic and family variables, academic performance, war stressors, home/community, school, and media violence exposure, self-image, and psychopathology.Methods
This cross-sectional study included 100 delinquent, incarcerated male adolescents and 100 matched schoolchildren from Croatia. It lasted from January 2008 to June 2009, and used socio-demographic questionnaire, questionnaire on children’s stressful and traumatic war experiences, exposure to violence scale, the Offer Self-Image Questionnaire, and Youth Self-Report Questionnaire.Results
Logistic regression analysis showed that delinquency in incarcerated adolescents was more likely related to having parents who did not live together (odds ratio [OR] 2.40; confidence interval [CI] 1.18-4.90, P = 0.015), being more exposed to violence at home/community (OR 3.84; CI 1.58-9.34, P = 0.003), and having poorer self-image (OR 1.09; CI = 1.03-1.16, P < 0.002).Conclusion
Preventive and therapeutic interventions in incarcerated delinquents should be specifically targeted toward single parenthood, family factors, trauma oriented interventions, and focused on multiple dimensions of self-concept of adolescents.Delinquency is associated with many risk factors, including demographic, genetic, and family characteristics (single parenthood) or academic performance. Many studies have focused on exposure to various forms of violence – in the family or home; community and neighborhood; in school and peer groups; and the media, but other risk factors have also found to be important, such as poorer self-image, various forms of psychopathology, and social characteristics (neighborhoods characterized by poverty) (1-15). Most of the studies dealing with delinquency aim to develop therapeutic interventions in relation to the obtained factors or mediators (9,11,16).There are relatively few studies on incarcerated adolescents. Many report on delinquents’ traumatic experiences, posttraumatic stress disorder, and importance of developmental tasks of adolescence and parental monitoring (14,17,18). Therapeutic interventions are specifically directed toward assessment and intervention of trauma and psychopathology, and family interventions are used very often.There are not many studies on delinquents in Croatia and most of them deal with a model that takes into account the interplay between protective and risk factors (19-21). Factors that are often mentioned are parental distrust and punishment, and family dysfunctionality (22-24). The prevalence of delinquency in the last few years has not been reducing (25), which suggests that the current preventive and therapeutic efforts have not been sufficient (25). Another important factor that has to be considered when studying delinquency in Croatia is the influence of Croatian War for Independence 1991-1995. The relationship between war experiences (direct or indirect) and the development of delinquency in adolescents has been relatively rarely described, with contradictory findings. Some studies found no association between the impact of war and bullying (26), whereas others found a relationship between aggressiveness in child refugees and their past war experiences (27) or experiences of their parents, war veterans (28). Besides war-related violence, we expected that delinquency was related to the exposure to other types of violence, eg, violence at home (29). Finally, we also expected an association with poorer self-image (8) and the presence of significant psychopathological syndromes (7).Our aim was therefore to examine the relationship between demographic, family factors, academic performance, exposure to violence in different contexts (home, community, school, media, war related stress), psychopathology, and delinquency. 相似文献60.
Goran Brajušković Zorana Nikolić Vinka Vukotić Snežana Cerović Dušanka Savić‐Pavićević Stanka Romac 《International journal of experimental pathology》2013,94(6):355-361
Genome-wide association studies (GWAS) have identified over 46 SNPs associated with human prostate cancer (PCa). Some studies have shown correlation of the nitric oxide synthase (NOS) NOS3 gene polymorphisms with the risk and/or progression of PCa. This study aimed to evaluate the association of NOS3 gene polymorphisms (−786T>C, −764A>G, −714G>T, −690C>T, −649G>A and 894G>T) with PCa risk and progression. 150 patients with PCa, 150 patients with BPH and 100 age-matched healthy controls were recruited in this study. Genotyping of promoter polymorphisms was performed by bi-directional DNA sequencing, and for 894G>T by RFLP analysis. There was no significant association between the alleles and genotypes of these genetic variants and PCa risk. For −786T>C polymorphism, we found that C allele is associated with absence of metastases, assuming dominant genetic model (P = 0.049; OR, 0.50; 95% CI, 0.25–1.00). It was found that, compared with NOS3 −690C>T variant CC genotype, CT and TT genotypes confer decreased risk of developing metastases (dominant model, P = 0.015, OR, 0.24; 95% CI, 0.07–0.88) and show association with low clinical tumour stage, compared with stages T3 and T4 (dominant model, P = 0.046, OR, 0.20; 95% CI, 0.04–1.02). Genetic variants −764A>G, −714G>T, −649G>A were not detected in our study group. There is evidence of an inverse correlation of the NOS3 894G>T minor allele with high serum PSA (>20 ng/ml) (dominant model, P = 0.013, OR, 0.37; 95% CI, 0.17–0.82). Our results suggest that NOS3 gene polymorphisms are genetic susceptibility factors for the progression of PCa and patient outcome. 相似文献